A belt for a shoe-press of a paper machine having water drain grooves which are resistant to the occurrence of cracks in side walls of the water drain grooves. The surface condition of the water drain grooves side wall is arranged to be a pear-skin state having minute unevenness. Preferably the surface has an average surface roughness in a range of 10 to 50 micrometers in at least the upper two thirds of the total distance (depth) of the side walls of the water drain grooves between the top of the groove and the bottom thereof. The water drain grooves can be manufactured by rotary cutting blades disposed in a position in contact with a roll around which a belt is wound. The roll and the rotary cutting blades rotate simultaneously and a groove cutting device is shifted in the width direction of the belt so that water drain grooves are formed in the belt. The belt running speed on the roll is set at 2 to 20 m/min, preferably 5 to 15 m/min, and rotation speed of the rotary cutting blades is set at 1,000 to 8,000 rpm.